Re: [PATCH 00/11] Use global pages with PTI

From: Linus Torvalds
Date: Fri Mar 23 2018 - 14:26:57 EST


On Fri, Mar 23, 2018 at 10:44 AM, Dave Hansen
<dave.hansen@xxxxxxxxxxxxxxx> wrote:
>
> This adds one major change from the last version of the patch set
> (present in the last patch). It makes all kernel text global for non-
> PCID systems. This keeps kernel data protected always, but means that
> it will be easier to find kernel gadgets via meltdown on old systems
> without PCIDs. This heuristic is, I think, a reasonable one and it
> keeps us from having to create any new pti=foo options

Sounds sane.

The patches look reasonable, but I hate seeing a patch series like
this where the only ostensible reason is performance, and there are no
performance numbers anywhere..

Linus